670 results on '"Wędrychowicz A"'
Search Results
2. Should we routinely assess hypothalamic–pituitary–adrenal axis in pediatric patients with Prader–Willi syndrome?
- Author
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Anna Maria Wędrychowicz, Katarzyna Doleżal-Ołtarzewska, Agata Zygmunt-Górska, Anna Urszula Kalicka-Kasperczyk, Katarzyna Tyrawa, Malgorzata Wojcik, Dominika Janus, Adrianna Kot, Agnieszka Lecka-Ambroziak, Elzbieta Petriczko, Joanna Wielopolska, and Jerzy Starzyk
- Subjects
Prader-Willi syndrome (PWS) ,hypothalamic-pituitary-adrenal axis (HPAA) ,central adrenal insufficiency (CAI) ,low-dose ACTH test (LDAT) ,glugacon stimulation test (GST) ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
BackgroundIt has been reported that central adrenal insufficiency (CAI) in pediatric patients (pts) with Prader–Willi syndrome (PWS) may be a potential cause of their sudden death. In addition, the risk of CAI may increase during treatment with recombinant human growth hormone (rhGH).ObjectiveTo prevent both over- and undertreatment with hydrocortisone, we evaluated the prevalence of CAI in a large multicenter cohort of pediatric pts with PWS analyzing adrenal response in the low-dose ACTH test (LDAT) and/or the glucagon stimulation test (GST) and reviewing the literature.MethodsA total of 46 pts with PWS were enrolled to the study, including 34 treated with rhGH with a median dose of 0.21 mg/kg/week. LDAT was performed in 46 pts, and GST was carried out in 13 pts. Both tests were conducted in 11 pts. The tests began at 8:00 a.m. Hormones were measured by radioimmunoassays. Serum cortisol response >181.2 ng/mL (500 nmol/L) in LDAT and >199.3 ng/mL (550 nmol/L) in GST was considered a normal response. Additionally, cortisol response delta (the difference between baseline and baseline) >90 ng/mL and doubling/tripling of baseline cortisol were considered indicators of normal adrenal reserve.ResultsThree GSTs were not diagnostic (no hypoglycemia obtained). LDAT results suggested CAI in four pts, but in two out of four pts, and CAI was excluded in GST. GST results suggested CAI in only one patient, but it was excluded in LDAT. Therefore, CAI was diagnosed in 2/46 pts (4.3%), 1 treated and 1 untreated with rhGH, with the highest cortisol values of 162 and 175 ng/dL, but only in one test. However, in one of them, the cortisol delta response was >90 ng/mL and peak cortisol was more than tripled from baseline. Finally, CAI was diagnosed in one patient treated with rhGH (2.2%).ConclusionWe present low prevalence of CAI in pediatric pts with PWS according to the latest literature. Therefore, we do not recommend to routinely screen the function of the hypothalamic–pituitary–adrenal axis (HPAA) in all pts with PWS, both treated and untreated with rhGH. According to a review of the literature, signs and symptoms or low morning ACTH levels suggestive of CAI require urgent and appropriate diagnosis of HPAA by stimulation test. Our data indicate that the diagnosis of CAI should be confirmed by at least two tests to prevent overtreatment with hydrocortisone.
- Published
- 2024
- Full Text
- View/download PDF
3. Endogenous Cannabinoids in Crohn’s Disease
- Author
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Michał S. Bochenek, Jan T. Tomasik, Andrzej Wędrychowicz, and Przemysław J. Tomasik
- Subjects
2-arachidonoylglycerol ,anandamide ,endocannabinoid ,inflammatory bowel disease ,adolescence ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Background: An increasing number of people around the world suffer from Crohn’s disease (CD), one of the inflammatory bowel diseases (IBDs). Recent evidence suggests that the endogenous cannabinoid system plays an important role in IBD. The main endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), are ligands of the CB1 and CB2 receptors that are expressed on immune cells. These receptors as well as endocannabinoids are believed to mediate inflammatory activity and participate in the pathophysiology of CD. Objective: Very little is known about the secretion of endogenous cannabinoids throughout the course of CD. Therefore, the aim of this study was to determine and analyze the 2-AG and AEA concentrations in children who suffered from CD. Methods: We studied 34 adolescents with CD, mean age 13.5 years ± 2.0. Blood samples were collected three times in the active phase of the disease (during admission to hospital, before treatment), 2–4 weeks later, during the treatment and clinical improvement of the patients, and 3–6 months later, in the period of remission. The control group included 33 healthy teenagers of the same age who were examined once. In all patients, fasting blood samples were collected in the morning. 2AG and AEA concentrations in serum were measured using EIA kits (Abclonal, Woburn, MA, USA and ELK Biotechnology Co., Ltd. Wuhan, China, respectively). Results: The median 2-AG concentration in the study group was stable: acute phase 907.4 [379.3; 1300.5] pg/mL, during treatment 715.1 [416.7; 1302.5] pg/mL; remission 991.1 [381.1; 1652.5] pg/mL, and similar to the values observed in the control group 761.8 [504.3; 1497.0] pg/mL. No significant differences were found between the results obtained at all time points in the study group and compared to the control group (in all cases p > 0.44). In the case of AEA, in the study group before treatment, the median concentration was 2.63 [2.24; 2.79] ng/mL and similar to values obtained during treatment 2.56 [2.33; 3.06] ng/mL, and in remission, with 2.61 [2.46; 2.85] ng/mL. All these concentrations were lower compared to the values measured in the control group of 3.18 [2.57; 3.88] ng/mL (p = 0.023, p = 0.035, p = 0.056, respectively). Conclusions: While 2-AG levels remained stable throughout the disease course and were comparable to controls, AEA concentrations were consistently lower in CD patients. Therefore, therapeutic interventions aimed at increasing AEA-related signaling, such as administration of its analogues or fatty acid amide hydrolase inhibitors, may improve symptoms associated with Crohn’s disease in children.
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- 2024
- Full Text
- View/download PDF
4. Agent Based Model of Elementary School Group Learning – A Case Study
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Wędrychowicz, Barbara, Maleszka, Marcin, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Nguyen, Ngoc Thanh, editor, Botzheim, János, editor, Gulyás, László, editor, Núñez, Manuel, editor, Treur, Jan, editor, Vossen, Gottfried, editor, and Kozierkiewicz, Adrianna, editor
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- 2023
- Full Text
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5. Liver fibrosis assessment in pediatric population - can ultrasound elastography be an alternative method to liver biopsy? A systematic review
- Author
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Medyńska-Przęczek, Aleksandra, Stochel-Gaudyn, Anna, and Wędrychowicz, Andrzej
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- 2024
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6. The Influence of Various Welding Methods on the Microstructure and Mechanical Properties of 316Ti Steel
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Piotr Noga, Tomasz Skrzekut, Maciej Wędrychowicz, Marek St. Węglowski, and Marcel Wiewióra
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316Ti steel ,MIG ,TIG ,EBW and PAW welding ,mechanical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Austenitic stainless steels are very popular due to their high strength properties, ductility, excellent corrosion resistance and work hardening. This paper presents the test results for joining AISI 316Ti austenitic steel. The technologies used for joining were the most popular welding techniques such as TIG (welding with a non-consumable electrode in the shield of inert gases), MIG (welding with a consumable electrode in the shield of inert gases) as well as high-energy EBW welding (Electron Beam Welding) and plasma PAW (plasma welding). Microstructural examinations in the face, center and root areas of the weld revealed different contents of delta ferrite with skeletal or lathy ferrite morphology. Additionally, the presence of columnar grains at the fusion line and equiaxed grains in the center of the welds was found. Microstructural, X-ray and ferroscope tests showed the presence of different delta ferrite contents depending on the technology used. The highest content of delta ferrite was found in the TIG and PAW connectors, approximately 5%, and the lowest in the EBW connector, approximately 2%. Based on the tests carried out on the mechanical properties, it was found that the highest properties were achieved by the MIG joint (Rm, 616, Rp0.2 = 335 MPa), while the lowest were achieved by the PAW joint (Rm = 576, Rp0.2 = 315 MPa).
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- 2024
- Full Text
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7. Agent Based Model of Elementary School Group Learning – A Case Study
- Author
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Wędrychowicz, Barbara, primary and Maleszka, Marcin, additional
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- 2023
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8. Agent Based Model of Elementary School Group Learning
- Author
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Wedrychowicz, Barbara, Maleszka, Marcin, Sinh, Nguyen Van, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Szczerbicki, Edward, editor, Wojtkiewicz, Krystian, editor, Nguyen, Sinh Van, editor, Pietranik, Marcin, editor, and Krótkiewicz, Marek, editor
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- 2022
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9. Recycling of Electrical Cables—Current Challenges and Future Prospects
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Maciej Wędrychowicz, Jagoda Kurowiak, Tomasz Skrzekut, and Piotr Noga
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plastic materials ,recycling/recovery ,mechanical processing ,copper ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Civilization and technical progress are not possible without energy. Dynamic economic growth translates into a systematic increase in demand for electricity. Ensuring the continuity and reliability of electricity supplies is one of the most important aspects of energy security in highly developed countries. Growing energy consumption results not only in the need to build new power plants but also in the need to expand and increase transmission capacity. Therefore, large quantities of electric cables are produced all over the world, and after some time, they largely become waste. Recycling of electric cables focuses on the recovery of metals, mainly copper and aluminum, while polymer insulation is often considered waste and ends up in landfills. Currently, more and more stringent regulations are being introduced, mainly environmental ones, which require maximizing the reduction in waste. This article provides a literature review on cable recycling, presenting the advantages and disadvantages of various recycling methods, including mechanical and material recycling. It has been found that currently, there are very large possibilities for recycling cables, and intensive scientific work is being carried out on their development, which is consistent with global climate policy.
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- 2023
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10. Recycling of Hard Disk Drive Platters via Plastic Consolidation
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Tomasz Skrzekut, Maciej Wędrychowicz, and Andrzej Piotrowicz
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HDD platters ,plastic consolidation ,recycling ,mechanical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The paper presents the comparison of two methods of recycling aluminum from HDD platters—the melting method and the method of plastic consolidation. The main elements of HDD memory, i.e., data carriers (platters), were examined via the percentage share of the total HDD mass and also via EDS analysis. The most common are platters made of the aluminum alloy series 5XXX, which are covered with a thin magnetic layer made of nickel. The research involved removing data carriers from about 30 HDDs and fragmenting them. The next step was to divide the platters into three groups; one was melted, the second was subjected to plastic consolidation, and the third group was fragmented into chips and also subjected to the consolidation process. Then, in the process of co-extrusion, rods were extruded from each material, and were subjected to EDS analysis, microstructure testing, Vickers hardness, and uniaxial tensile tests, and then the obtained results were compared. The obtained results of the microstructural tests in the case of gravity cast material confirmed the presence of the Al3Ni globular phase in the matrix. In the case of pressed and extruded materials, the Al3Ni phase appeared at the Ni-AlMg contact. After plastic consolidation, all the tested rods were characterized by their comparable strength properties (a tensile strength of 250 MPa and yield strength of 105 MPa).
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- 2023
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11. A Numerical and Experimental Analysis of the Mechanical Behavior of the Aluminum Beverage Can with Internal Varnish Layers during Axial Load Force Testing
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Przemysław Wędrychowicz, Piotr Kustra, and Andrij Milenin
- Subjects
3104 H19 ,beverage can ,internal varnish ,axial load force ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
This article presents a numerical and experimental investigation into the impact of can wall thickness and the internal varnish layer thickness on the results of an axial load force test. This study also shows the levels of thermal stresses that emerge after the drying of varnish coating, and how they affect the results of the axial load force test. This research involves the development of suitable numerical models and the experimental acquisition of stress–deformation relationships for the both can material, aluminum, and the varnish. The numerical simulation of the axial load force test has been verified through experimental tests, with a resulting difference of 8.9% between the two sets of results. The findings highlight that changes in the can wall thickness have a more pronounced effect on test outcomes compared to variations in the varnish thickness. Specifically, an increase in the can wall thickness from 90 µm to 100 µm results in a substantial 116 N increase in the force required for a can to collapse. Nevertheless, the presence of a 5 µm varnish layer also contributes measurably, increasing the can’s collapse force by 21 N. These results offer valuable practical insights for manufacturers, enabling them to effectively optimize can strength characteristics.
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- 2023
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12. Affected brother as the highest risk factor of type 1 diabetes development in children and adolescents: One center data before implementing type 1 diabetes national screening.
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Wędrychowicz, Anna, Grzelak, Teresa, Pietraszek, Alicja, Skrzyszowska, Maria, Minasjan, Mari, and Starzyk, Jerzy B.
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TYPE 1 diabetes ,TYPE 2 diabetes ,DIABETES in children ,NUCLEAR families ,FAMILY history (Sociology) - Abstract
Background. There is an increased risk for childhood type 1 diabetes (T1D) when T1D and type 2 diabetes (T2D) are reported in relatives. Objectives. Our objective was to evaluate current family risk factors for T1D development before implementing a national screening program for T1D. Materials and methods. A population of 879 Caucasian children and adolescents with T1D and 286 healthy controls were enrolled in the study. All participants completed the same questionnaire, which collected information about family history of diabetes over 3 generations. In statistical analyses, frequency tables and Χ2 tests evaluated possible multicollinearity among risk factors that were significantly associated with the outcomes. Results. Family history of diabetes was more frequent in controls (n = 75, 26.2%) than in patients with T1D (n = 146, 16.6%, odds ratio (OR) = 1.785, 95% confidence interval (95% CI): 1.299-2.452, degrees of freedom (df) = 12.976, p = 0.004), especially with a family history of T2D (n = 62, 21.7% compared to n = 79, 9.0%, respectively, OR = 2.803, 95% CI: 1.948-4.034, df = 32.669, p < 0.001). Also, there was a tendency for the nuclear family of T1D patients to be more frequently affected by T1D (n = 74, 8.4%) than the controls (n = 15, 5.2%, OR = 1.605, 95% CI: 0.937-2.751, df = 3.081, p = 0.079). The risk of T1D was associated with the closest family members being affected and accelerated over generations. Indeed, it was highest in siblings, especially brothers (OR = 12.985, 95% CI: 0.782-215.743, Fisher's test: p < 0.001). A positive family history of T2D burden among second-degree relatives was 2.728 times more frequent in the control group than in the T1D group (OR = 2.728; 95% Cl: 1.880-3.962, p < 0.001). Furthermore, a positive family history of T1D among first-degree relatives was less frequent in the controls than in the T1D group (OR = 0.124; 95% Cl: 0.030-0.516, p = 0.004). Conclusions. A family history of T1D, but not T2D, is a significant risk factor for T1D development. Indeed, the priority in screening for T1D should be given to first-degree relatives of T1D patients, starting from siblings. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Endogenous Cannabinoids in Crohn's Disease.
- Author
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Bochenek, Michał S., Tomasik, Jan T., Wędrychowicz, Andrzej, and Tomasik, Przemysław J.
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CROHN'S disease ,INFLAMMATORY bowel diseases ,JUVENILE diseases ,DISEASE progression ,HOSPITAL admission & discharge - Abstract
Background: An increasing number of people around the world suffer from Crohn's disease (CD), one of the inflammatory bowel diseases (IBDs). Recent evidence suggests that the endogenous cannabinoid system plays an important role in IBD. The main endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), are ligands of the CB1 and CB2 receptors that are expressed on immune cells. These receptors as well as endocannabinoids are believed to mediate inflammatory activity and participate in the pathophysiology of CD. Objective: Very little is known about the secretion of endogenous cannabinoids throughout the course of CD. Therefore, the aim of this study was to determine and analyze the 2-AG and AEA concentrations in children who suffered from CD. Methods: We studied 34 adolescents with CD, mean age 13.5 years ± 2.0. Blood samples were collected three times in the active phase of the disease (during admission to hospital, before treatment), 2–4 weeks later, during the treatment and clinical improvement of the patients, and 3–6 months later, in the period of remission. The control group included 33 healthy teenagers of the same age who were examined once. In all patients, fasting blood samples were collected in the morning. 2AG and AEA concentrations in serum were measured using EIA kits (Abclonal, Woburn, MA, USA and ELK Biotechnology Co., Ltd. Wuhan, China, respectively). Results: The median 2-AG concentration in the study group was stable: acute phase 907.4 [379.3; 1300.5] pg/mL, during treatment 715.1 [416.7; 1302.5] pg/mL; remission 991.1 [381.1; 1652.5] pg/mL, and similar to the values observed in the control group 761.8 [504.3; 1497.0] pg/mL. No significant differences were found between the results obtained at all time points in the study group and compared to the control group (in all cases p > 0.44). In the case of AEA, in the study group before treatment, the median concentration was 2.63 [2.24; 2.79] ng/mL and similar to values obtained during treatment 2.56 [2.33; 3.06] ng/mL, and in remission, with 2.61 [2.46; 2.85] ng/mL. All these concentrations were lower compared to the values measured in the control group of 3.18 [2.57; 3.88] ng/mL (p = 0.023, p = 0.035, p = 0.056, respectively). Conclusions: While 2-AG levels remained stable throughout the disease course and were comparable to controls, AEA concentrations were consistently lower in CD patients. Therefore, therapeutic interventions aimed at increasing AEA-related signaling, such as administration of its analogues or fatty acid amide hydrolase inhibitors, may improve symptoms associated with Crohn's disease in children. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Should we routinely assess hypothalamic-pituitary-adrenal axis in pediatric patients with Prader-Willi syndrome?
- Author
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Wędrychowicz, Anna Maria, Doleżal-Ołtarzewska, Katarzyna, Zygmunt-Górska, Agata, Kalicka-Kasperczyk, Anna Urszula, Tyrawa, Katarzyna, Wojcik, Malgorzata, Janus, Dominika, Kot, Adrianna, Lecka-Ambroziak, Agnieszka, Petriczko, Elzbieta, Wielopolska, Joanna, and Starzyk, Jerzy
- Subjects
SUDDEN death ,PRADER-Willi syndrome ,HYPOTHALAMIC-pituitary-adrenal axis ,CHILD patients ,HUMAN growth hormone ,LITERATURE reviews - Abstract
Background: It has been reported that central adrenal insufficiency (CAI) in pediatric patients (pts) with Prader-Willi syndrome (PWS) may be a potential cause of their sudden death. In addition, the risk of CAI may increase during treatment with recombinant human growth hormone (rhGH). Objective: To prevent both over- and undertreatment with hydrocortisone, we evaluated the prevalence of CAI in a large multicenter cohort of pediatric pts with PWS analyzing adrenal response in the low-dose ACTH test (LDAT) and/or the glucagon stimulation test (GST) and reviewing the literature. Methods: A total of 46 pts with PWS were enrolled to the study, including 34 treated with rhGH with a median dose of 0.21 mg/kg/week. LDAT was performed in 46 pts, and GST was carried out in 13 pts. Both tests were conducted in 11 pts. The tests began at 8:00 a.m. Hormones were measured by radioimmunoassays. Serum cortisol response >181.2 ng/mL (500 nmol/L) in LDAT and >199.3 ng/mL (550 nmol/L) in GST was considered a normal response. Additionally, cortisol response delta (the difference between baseline and baseline) >90 ng/mL and doubling/tripling of baseline cortisol were considered indicators of normal adrenal reserve. Results: Three GSTs were not diagnostic (no hypoglycemia obtained). LDAT results suggested CAI in four pts, but in two out of four pts, and CAI was excluded in GST. GST results suggested CAI in only one patient, but it was excluded in LDAT. Therefore, CAI was diagnosed in 2/46 pts (4.3%), 1 treated and 1 untreated with rhGH, with the highest cortisol values of 162 and 175 ng/dL, but only in one test. However, in one of them, the cortisol delta response was >90 ng/mL and peak cortisol was more than tripled from baseline. Finally, CAI was diagnosed in one patient treated with rhGH (2.2%). Conclusion: We present low prevalence of CAI in pediatric pts with PWS according to the latest literature. Therefore, we do not recommend to routinely screen the function of the hypothalamic-pituitary-adrenal axis (HPAA) in all pts with PWS, both treated and untreated with rhGH. According to a review of the literature, signs and symptoms or low morning ACTH levels suggestive of CAI require urgent and appropriate diagnosis of HPAA by stimulation test. Our data indicate that the diagnosis of CAI should be confirmed by at least two tests to prevent overtreatment with hydrocortisone. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
15. Microstructure and Mechanical Properties of Al-Si Alloys Produced by Rapid Solidification and Hot Extrusion
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Piotr Noga, Tomasz Skrzekut, and Maciej Wędrychowicz
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Al-Si aluminum alloy ,melt-spinning ,shape factor ,mechanical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The paper presents the results of tests of rapid solidification (RS) aluminum alloys with the addition of silicon (5%, 11%, and 20%). Casting by melt-spinning on the surface of an intensively cooled copper cylinder allowed to obtain a metallic material in the form of flakes, which were then consolidated in the process of pressing and direct extrusion. The effect of refinement on structural components after rapid solidification was determined. Rapidly solidified AlSi materials are characterized by a comparable size of Si particles, regardless of the silicon content, and the shape of these particles is close to spheroidal. Not only Si particles are fragmented, but also the Al-Si-Fe phase, which also changed its shape from irregular with sharp edges to regular and spherical. The melt-spinning process resulted in a fine-grained structure compared to materials obtained by gravity-casting and extrusion. The influence of the high-temperature compression test on the mechanical properties of rapidly solidified materials was analyzed, and the results were compared with those of gravity-cast materials. An increase in strength properties was found in the case of the AlSi5 RS alloy by 20%, in the case of AlSi11RS by 25%, and in the case of the alloy containing 20% Si by as much as 86% (tensile test). On the basis of the homogeneity of the particle distribution determined by the SEM method, it was found that rapid solidification is an effective method of increasing the strength properties and improving the plastic properties of Al-Si alloys.
- Published
- 2023
- Full Text
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16. Research of Friction Stir Welding (FSW) and Electron Beam Welding (EBW) Process for 6082-T6 Aluminum Alloy
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Piotr Noga, Tomasz Skrzekut, Maciej Wędrychowicz, Marek St. Węglowski, and Aleksandra Węglowska
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6082-T6 aluminum alloy ,FSW ,EBW ,microstructure ,mechanical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The paper presents the results of the joining tests of the EN AW-6082 T6 alloy. The materials were joined using the EBW high-energy (electron beam welding) and friction stir welding (FSW) methods. In the case of FSW welding, the following parameters were used: the linear speed was 355 mm/min, and the rotational speed of the welding tool was 710. In the case of EBW welding, the following parameters were used: accelerating voltage U = 120 kV, beam intensity I = 18.7 mA, welding speed v = 1600 mm/min and, in the case of a smoothing weld, U = 80 kV, beam intensity I = 17 mA, and welding speed v = 700 mm/min. Comprehensive microstructural tests of all welded joints (MO, SEM and TEM) and mechanical property tests (tensile and hardness tests) were carried out. The topographies of the fractures after the tensile test were also examined. Based on the results, it was found that the strength properties of the EBW joint were reduced by 23% and the FSW joint by 38% compared to the base material. A decrease in elongation was also noted, with an FSW elongation of 7.2% and an elongation of 2.7% for EBW. In the case of the EBW joint, magnesium evaporation was found in the weld during welding, while in the FSW joint, the dissolution of the Mg2Si particles responsible for strengthening the material during heat treatment to the T6 state was observed.
- Published
- 2023
- Full Text
- View/download PDF
17. Prevention and Health Benefits of Prebiotics, Probiotics and Postbiotics in Acute Lymphoblastic Leukemia
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Adrian Martyniak, Zuzanna Zakrzewska, Magdalena Schab, Aleksandra Zawartka, Andrzej Wędrychowicz, Szymon Skoczeń, and Przemysław J. Tomasik
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microbiota ,gastrointestinal tract ,inulin ,pectin ,anticancer ,lactobacillus ,Biology (General) ,QH301-705.5 - Abstract
Acute lymphoblastic leukemia (ALL) is the most common type of leukemia in children, comprising 75–85% of cases. Aggressive treatment of leukemias includes chemotherapy and antibiotics that often disrupt the host microbiota. Additionally, the gut microbiota may play a role in the development and progression of acute leukemia. Prebiotics, probiotics, and postbiotics are considered beneficial to health. The role of prebiotics in the treatment and development of leukemia is not well understood, but inulin can be potentially used in the treatment of leukemia. Some probiotic bacteria such as Lactobacillus shows anticancer activity in in vitro studies. Additionally, Bifidobacterium spp., as a consequence of the inhibition of growth factor signaling and mitochondrial-mediated apoptosis, decrease the proliferation of cancer cells. Many bacterial metabolites have promising anticancer potential. The available research results are promising. However, more research is needed in humans, especially in the child population, to fully understand the relationship between the gut microbiota and acute leukemia.
- Published
- 2023
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- View/download PDF
18. Endogenous Opioids in Crohn’s Disease
- Author
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Adrian Martyniak, Andrzej Wędrychowicz, and Przemysław J. Tomasik
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endogenous opioids ,inflammatory bowel disease ,endorphin ,enkephalin ,dynorphin ,Biology (General) ,QH301-705.5 - Abstract
Caring for patients with Crohn’s disease (CD) is a serious challenge in modern medicine. The increasing incidence of CD among adolescents and the severe course of the disease create the need for new methods of diagnosis and therapy. Endogenous opioids are a group of low molecular weight chemical compounds with analgesic and anti-inflammatory properties. Endorphins, enkephalins, and dynorphins may have potentially beneficial effects on the course of CD. Previous research data on this topic are inconsistent. Some authors have reported an increase in the concentration of leukocytes during the course of inflammatory bowel disease (IBD) while others have described a downward trend, explained by DPP-IV enzyme activity. Even fewer data are available on plasma endo-opioid level. There is also a lack of comprehensive studies that have assessed the endo-opioid system in patients with IBD. Therefore, the objective of this study was to measure the serum concentrations of human β-endorphin, human proenkephalin (A), and human big dynorphin in CD patients in the acute phase of the disease, during hospital treatment, and in the remission state. All determinations were performed using ELISA kits. The results of our study showed that the concentrations of all the tested endo-opioids, especially β-endorphin and proenkephalin (A), were reduced in adolescents with CD compared to those in the healthy control group, during the acute phase of the disease, and in the remission state. Modulation of the endogenous opioid system and the use of selective nonnarcotic agonists of opioid receptors seems to be promising goals in the future treatment of CD.
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- 2023
- Full Text
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19. The enteroendocrine-osseous axis in patients with long-term type 1 diabetes mellitus
- Author
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Katra, Barbara, Fedak, Danuta, Matejko, Bartłomiej, Małecki, Maciej T., and Wędrychowicz, Anna
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- 2021
- Full Text
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20. Non-linear control of a gear shift process in a dual-clutch transmission based on a neural engine model
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Bera, Piotr, Sikora, Wojciech, and Wędrychowicz, Dariusz
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- 2021
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21. Distortion inequality for a Markov operator generated by a randomly perturbed family of Markov Maps in ℝd
- Author
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Bugiel Peter, Wędrychowicz Stanisław, and Rzepka Beata
- Subjects
markov operator ,markov maps ,discrete semi-dynamical systems ,radon-nikodym derivative ,frobenius-perron operator ,primary 37a30 ,secondary 47a35 ,Analysis ,QA299.6-433 - Abstract
Asymptotic properties of the sequences
- Published
- 2021
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22. On some results on the stability of Markov operators
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Wȩdrychowicz, Stanisław and Wiśnicki, Andrzej
- Subjects
Mathematics - Probability ,Mathematics - Functional Analysis - Abstract
We formulate a criterion for the existence of an invariant measure for a Feller semigroup defined on a metric space with the e-property for bounded continuous functions and use it to prove the asymptotic stability of a semigroup satisfying a lower bound condition. Our results complement those of A. Lasota and J. A. Yorke in proper metric spaces and of T. Szarek in Polish spaces., Comment: 14 pages, revised version, to appear in Studia Mathematica
- Published
- 2016
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23. Difficulties in Interpreting IGF-1 Levels in Short Stature Children Born Small for Gestational Age (SGA) Treated with Recombinant Human Growth Hormone (rhGH) Based on Data from Six Clinical Centers in Poland
- Author
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Marta Glińska, Mieczysław Walczak, Beata Wikiera, Beata Pyrżak, Anna Majcher, Monika Paluchowska, Aneta Gawlik, Aleksandra Antosz, Marcin Kusz, Artur Bossowski, Karolina Stożek, Anna Wędrychowicz, Jerzy Starzyk, and Elżbieta Petriczko
- Subjects
SGA ,IGF-1 ,recombinant human growth hormone ,Medicine - Abstract
The assessment of IGF-1 concentrations is one of the parameters used for evaluating response to rhGH treatment. An increase in IGF-1 concentration positively correlates with growth improvement, whereas IGF-1 concentrations significantly above the reference range may increase the risk of possible side effects. The aim of this study was to evaluate the IGF-1 local reference ranges for the rhGH treatment centers concerned and to compare these values with the population reference ranges. A retrospective analysis was conducted on auxological data from 229 SGA patients who received rhGH treatment between 2016 and 2020 at six university clinical centers in Poland. The IGF-1 levels were assessed at baseline, after 12 and 24 months, and compared to the reference ranges provided by the local laboratory and to the population reference ranges. After 12 months, 56 patients (24%) presented IGF-1 values > 97th percentile for the local reference range, whereas only 8 (3.5%) did so using the population reference ranges; p < 0.001. After 24 months of treatment, the values were: 47 (33%) > 97th percentile by local vs. 6 (4.2%) by population standards; p < 0.001. Thirty-nine patients had rhGH dose reduced after 12 months, of whom twelve (25%) had IGF-1 > 97th percentile according to the local reference ranges and five (13%) > 97th percentile for the population. Our data suggest that different methods used to determine IGF-1 concentration and the different IGF-1 reference ranges result in a significant proportion of rhGH-treated children with elevated IGF-1 concentration and experiencing dose reductions, which may negatively affect growth rate.
- Published
- 2023
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24. Experimental Determination Influence of Flow Disturbances behind the Knife Gate Valve on the Indications of the Ultrasonic Flow Meter with Clamp-On Sensors on Pipelines
- Author
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Piotr Piechota, Piotr Synowiec, Artur Andruszkiewicz, Wiesław Wędrychowicz, Elżbieta Wróblewska, and Andrzej Mrowiec
- Subjects
ultrasonic flow meter ,clamp-on ,flow disturbance ,correction factor measurement error ,knife gate valve ,laser doppler anemometry ,Chemical technology ,TP1-1185 - Abstract
The aim of this work is to experimentally determine and evaluate the value of the correction factor for ultrasonic flow meters in order to improve their accuracy. This article concerns flow velocity measurement with the use of an ultrasonic flow meter in the area of disturbed flow behind the distorting element. Clamp-on ultrasonic flow meters are popular among measurement technologies due to their high accuracy and easy, non-invasive installation, because the sensors are mounted directly on the outer surface of the pipe. In industrial applications, installation space is usually limited and, therefore, flow meters frequently have to be mounted directly behind flow disturbances. In such cases, it is necessary to determine the value of the correction factor. The disturbing element was a knife gate valve, a valve often used in flow installations. Water flow velocity tests were performed using an ultrasonic flow meter with clamp-on sensors on the pipeline. The research was performed in 2 series of measurements with different Reynolds numbers of 35,000 and 70,000, which correspond to a velocity of approximately 0.9 m/s and 1.8 m/s. The tests were carried out at different distances from the source of interference, within the range of 3–15 DN (pipe nominal diameter). The position of the sensors at successive measurement points on the circuit of the pipeline was changed by 30 degrees. Flow velocity measurements were carried out for two different levels of the valve’s closure: 1/3 and 1/2 of the valve’s height. For the collected velocity values at single measurement points, the values of the correction coefficient, K, were determined. The results of the tests and calculations prove that compensation error of measurement performed behind the disturbance without keeping the required straight sections of the pipeline is possible by using the factor K*. The analysis of the results made it possible to identify the optimal measuring point at a distance from the knife gate valve as being smaller than specified in the standards and recommendations.
- Published
- 2023
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25. Fixed point of some Markov operator of Frobenius-Perron type generated by a random family of point-transformations in ℝd
- Author
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Bugiel Peter, Wędrychowicz Stanisław, and Rzepka Beata
- Subjects
markov operator ,markov maps ,fixed point ,radon-nikodym derivative ,frobenius-perron operator ,37a30 ,Analysis ,QA299.6-433 - Abstract
Existence of fixed point of a Frobenius-Perron type operator P : L1 ⟶ L1 generated by a family {φy}y∈Y of nonsingular Markov maps defined on a σ-finite measure space (I, Σ, m) is studied. Two fairly general conditions are established and it is proved that they imply for any g ∈ G = {f ∈ L1 : f ≥ 0, and ∥f∥ = 1}, the convergence (in the norm of L1) of the sequence {Pjg}j=1∞$\begin{array}{} \{P^{j}g\}_{j = 1}^{\infty} \end{array} $ to a unique fixed point g0. The general result is applied to a family of C1+α-smooth Markov maps in ℝd.
- Published
- 2021
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26. Indications for genetic diagnosis in children with growth hormone deficiency and born small for gestational age.
- Author
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Roztoczyńska, Dorota, Kot-Marchewczyk, Adrianna, Wędrychowicz, Anna, Dobosz, Artur, and Starzyk, Jerzy
- Subjects
SMALL for gestational age ,HUMAN growth hormone ,KALLMANN syndrome ,ANGIOKERATOMA corporis diffusum ,GROWTH of children ,PITUITARY dwarfism - Abstract
Introduction: The aim of the study is to analyze patients who do not respond adequately to human recombinant growth hormone (rhGH) treatment. Material and methods: Four boys were analyzed: three patients diagnosed with SNP at the ages of 1) 8 years and 2 months, 2) 13 years and 2 months, 3) 16 years and 6 months, and patient 4) at the age of 6 years and 11 months - born small for gestational age (SGA). They underwent rhGH treatment. Results: The expected growth improvement was not observed in all boys. Patient 1 was diagnosed with aortic coarctation, and after each attempt to increase the rhGH dose, nocturnal vomiting occurred - epilepsy was diagnosed. Patient 2 had severe foot pain. Patient 3 had delayed puberty - hypogonadotropic hypogonadism was diagnosed. Patient 4 had dysmorphic features. Genetic tests revealed the following: 1) mixed gonadal dysgenesis - modifying treatment; 2) Fabry disease - enzyme treatment and rhGH improved growth; 3) Kallmann syndrome - discontinuing rhGH for testosterone supplementation; 4) KBG syndrome. Conclusions: 1. The presence of dysmorphic features and symptoms atypical for growth hormone deficiencies could warrant genetic diagnostics before initiating treatment. 2. Lack of significant improvement in growth is an indication for reevaluation of patients who have not completed growth. 3. Genetic studies in this patient group often elucidate the causes of slow growth rate. 4. The case authors have developed a proposal for a multicentre program aimed at establishing indications for genetic diagnosis in children diagnosed with SNP and SGA treated with rhGH. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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27. The Influence of Various Welding Methods on the Microstructure and Mechanical Properties of 316Ti Steel.
- Author
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Noga, Piotr, Skrzekut, Tomasz, Wędrychowicz, Maciej, Węglowski, Marek St., and Wiewióra, Marcel
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ELECTRON beam welding ,PLASMA arc welding ,WELDING ,WELDED joints ,AUSTENITIC steel ,ELECTRIC arc - Abstract
Austenitic stainless steels are very popular due to their high strength properties, ductility, excellent corrosion resistance and work hardening. This paper presents the test results for joining AISI 316Ti austenitic steel. The technologies used for joining were the most popular welding techniques such as TIG (welding with a non-consumable electrode in the shield of inert gases), MIG (welding with a consumable electrode in the shield of inert gases) as well as high-energy EBW welding (Electron Beam Welding) and plasma PAW (plasma welding). Microstructural examinations in the face, center and root areas of the weld revealed different contents of delta ferrite with skeletal or lathy ferrite morphology. Additionally, the presence of columnar grains at the fusion line and equiaxed grains in the center of the welds was found. Microstructural, X-ray and ferroscope tests showed the presence of different delta ferrite contents depending on the technology used. The highest content of delta ferrite was found in the TIG and PAW connectors, approximately 5%, and the lowest in the EBW connector, approximately 2%. Based on the tests carried out on the mechanical properties, it was found that the highest properties were achieved by the MIG joint (R
m , 616, Rp0.2 = 335 MPa), while the lowest were achieved by the PAW joint (Rm = 576, Rp0.2 = 315 MPa). [ABSTRACT FROM AUTHOR]- Published
- 2024
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28. Analysis of the Accuracy of Liquid Flow Measurements by the Means of Ultrasonic Method in Non-standard Measurements Conditions
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Piechota, Piotr, Synowiec, Piotr, Andruszkiewicz, Artur, Wędrychowicz, Wiesław, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Ruediger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Liang, Qilian, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zhang, Junjie James, Series Editor, Hanus, Robert, editor, Mazur, Damian, editor, and Kreischer, Christian, editor
- Published
- 2019
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29. Measurements of Gas Streams with Disturbed Velocity Distribution by the Means of an Elbow Flowmeter
- Author
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Piechota, Piotr, Synowiec, Piotr, Andruszkiewicz, Artur, Wędrychowicz, Wiesław, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Ruediger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Liang, Qilian, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zhang, Junjie James, Series Editor, Hanus, Robert, editor, Mazur, Damian, editor, and Kreischer, Christian, editor
- Published
- 2019
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30. The Effect of Adding Iron Powder From Plasma Cutting on the Microstructure, Mechanical Properties of the Composite Based on Aluminum Powder Matrix Made Using Powder Metallurgy
- Author
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M. Wędrychowicz, A.W. Bydałek, P. Migas, T. Skrzekut, P. Noga, P. Madej, and A. Kałasznikow
- Subjects
al-fe composite ,iron powder ,plasma cutting ,aluminum matrix composites ,powder metallurgy ,mechanical properties ,Mining engineering. Metallurgy ,TN1-997 ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The paper presents the results of research on the effect of added iron powder from plasma cutting on the mechanical properties and structure of a composite rod based on aluminum powder. The iron powder came from plasma cutting of steel elements and was handed over by the enterprise “AK Anatol” from Żary. One of the ways to dispose of it is to use it as a filler in aluminum composite rods. Research shows that Fe can be distributed in aluminum evenly, and increase in mechanical properties is achieved at the expense of only a slight increase in density. The proposed system does not reduce the amount of waste produced by plasma cutting but finds a use for some of it. The sintering point of the powder required a strongly reducing atmosphere (PO2 < 10–50 atm) which seems virtually unachievable under laboratory conditions. The reinforcing mechanism is related to the fragmentation of the matrix aggregate particles and the uniform distribution of Fe particles in the aluminum matrix.
- Published
- 2020
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31. Immunization with the recombinant myosin regulatory light chain (FhrMRLC) in Adjuplex® adjuvant elicits a Th1-biased immune response and a reduction of parasite burden in Fasciola hepatica infected rats
- Author
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Buffoni, L., Piva, M.M., Baska, P., Januszkiewicz, K., Norbury, L.J., Prior, K.C., Dezen, D., Silva, A.S., Wedrychowicz, H., and Mendes, R.E.
- Published
- 2020
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- View/download PDF
32. Analysis of Multicriteria Optimisation in the Decopperisation Process of Flash Smelting Slags
- Author
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Wędrychowicz, M., primary and Bydałek, A.W., additional
- Published
- 2023
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33. Recycling of Hard Disk Drive Platters via Plastic Consolidation
- Author
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Skrzekut, Tomasz, primary, Wędrychowicz, Maciej, additional, and Piotrowicz, Andrzej, additional
- Published
- 2023
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34. Recycling of Electrical Cables—Current Challenges and Future Prospects
- Author
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Wędrychowicz, Maciej, primary, Kurowiak, Jagoda, additional, Skrzekut, Tomasz, additional, and Noga, Piotr, additional
- Published
- 2023
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35. A Numerical and Experimental Analysis of the Mechanical Behavior of the Aluminum Beverage Can with Internal Varnish Layers during Axial Load Force Testing
- Author
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Wędrychowicz, Przemysław, primary, Kustra, Piotr, additional, and Milenin, Andrij, additional
- Published
- 2023
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36. A few problems connected with invariant measures of Markov maps - verification of some claims and opinions that circulate in the literature
- Author
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Bugiel Peter, Wędrychowicz Stanisław, and Rzepka Beata
- Subjects
markov maps ,invariant measure ,expanding transformation ,recurrence ,aperiodicity ,28d05 ,37a99 ,26a18 ,Analysis ,QA299.6-433 - Abstract
It is well known that C2-transformation φ of the unit interval into itself with a Markov partition (2.1) π = {Ik : k ∈ K} admits φ-invariant density g (g ≥ 0, ∥g∥ = 1) if: (2.2) ∣(φn)′∣ ≥ C1 > 1 for some n (expanding condition); (2.3) ∣φ″(x)/(φ′(y))2∣ ≤ C2 < ∞ (second derivative condition); and (2.4) #π < ∞ or φ (Ik) = [0, 1], for each Ik ∈ π. If (2.4) is deleted, then the situation dramatically changes. The cause of this fact was elucidated in connection with so-called Adler’s Theorem ([1] and [2]).
- Published
- 2020
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37. Immune Dysregulation in Patients With Chromosome 18q Deletions—Searching for Putative Loci for Autoimmunity and Immunodeficiency
- Author
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Anna Hogendorf, Maciej Zieliński, Maria Constantinou, Robert Śmigiel, Jolanta Wierzba, Krystyna Wyka, Anna Wędrychowicz, Anna Jakubiuk-Tomaszuk, Edyta Budzynska, Malgorzata Piotrowicz, Beata S. Lipska-Ziętkiewicz, Ewa Kaczorowska, Agata Cieślikowska, Anna Kutkowska-Kaźmierczak, Jolanta Fijak-Moskal, Monika Kugaudo, Małgorzata Kosińska-Urbańska, Agnieszka Szadkowska, Maciej Borowiec, Maciej Niedźwiecki, Piotr Trzonkowski, and Wojciech Młynarski
- Subjects
18q deletion syndrome ,immune deficiency ,type 1 diabetes ,autoimmune diseases ,thyroiditis ,T regulatory cells ,Immunologic diseases. Allergy ,RC581-607 - Abstract
IntroductionAutoimmune disorders, IgA deficiency, and allergies seem to be common among individuals with 18q deletion syndrome [OMIM 601808]. We aimed to determine the prevalence, mechanism, and genetic background of autoimmunity, immune deficiency, and allergy in a cohort of patients with 18q deletions.Material and MethodsMedical registries and social media were used to recruit the patients. Microarray oligonucleotide comparative genomic hybridization (aCGH) (Agilent, Santa Clara, CA, USA) was performed in all patients to identify size and location of chromosome 18 deletion. Clinical evaluation and medical record collection were performed in each of the study participants. The history of autoimmune disorders, severe and/or recurrent infections, and symptoms of allergy were noted. Total immunoglobulin IgG, IgA, IgM, IgE, and IgG1-4 serum levels were measured using nephelometry and ELISA methods. Lymphocyte T subset phenotyping was performed in 24 subjects from 18q del cohort. To predict the most promising candidate genes, we used the ENDEAVOUR—a free web resource for gene prioritization.Results18q deletion was confirmed by means of array CGH analysis in 27 individuals, 15 (55.6%) females and 12 males, referred to the project by specialists in medical genetics, diabetology, or pediatric endocrinology between May 2015 and December 2019. The mean age at examination was 11.8 years (min–max: 4.0–33.5). Autoimmune disorders were present in 14/27 (51.8%) of the cohort. In eight of patients, symptoms of immune deficiency coexisted with autoimmunity. Allergy was reported in nine of 27 (33.4%) patients. Over 89% of patients presented with at list one type of immunoglobulin (IgA, IgM, IgG, IgE, and IgG1-4) deficiency and eight of 25 (32%) had abnormalities in at least two major immunoglobulin (IgG, IgA, IgM) measurements (CVID-like phenotype). Patients with 18q del exhibited a significantly decreased CD4, Treg FOXP3+, TregFOXP3+Helios+, and TemCD4 cell numbers in comparison with the control groups of 24 T1DM patients and 28 healthy controls.ConclusionsPatients with 18q deletions frequently suffer from autoimmune disorders, recurrent infections, and allergy due to immune dysregulation presenting with variable antibody deficiencies and T-regulatory cell deficiency (CD4+CD25+CD127lowFOXP3+). The spectrum of speculations regarding which gene might be responsible for such phenotype ranges from single gene haploinsufficiency to deletion of a cluster of immunogenes located distally to 18q21.
- Published
- 2021
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- View/download PDF
38. Determining the Mechanical Properties of Solid Plates Obtained from the Recycling of Cable Waste
- Author
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Maciej Wędrychowicz, Władysław Papacz, Janusz Walkowiak, Adam Bydałek, Andrzej Piotrowicz, Tomasz Skrzekut, Jagoda Kurowiak, Piotr Noga, and Mirosław Kostrzewa
- Subjects
plastic materials ,recycling/recovery ,mechanical processing ,mechanical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
In this article, the possibility of obtaining a solid plate from waste cable sheaths, by mechanical recycling, i.e., grinding, plasticising and pressing, is discussed—waste cable sheaths being pure PVC with a slight admixture of silicone. Press moulding was carried out under the following conditions: temperature 135 °C, heating duration 1 h and applied pressure 10 MPa. The yield point of the obtained solid plate obtained was 15.0 + −0.6 MPa, flexural strength 0.94 MPa, yield point 0.47 MPa and Charpy’s impact strength 5.1 kJ/m2. The resulting solid plate does not differ significantly from the input material, in terms of mechanical strength, so, from the point of view of strength, that is, from a technical point of view, such promising processing of waste cables can be carried out successfully in industrial practice.
- Published
- 2022
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- View/download PDF
39. Electron Paramagnetic Resonance Study of PbSe, PbTe, and PbTe:In Semiconductors Obtained by the Pulsed Laser Deposition Method
- Author
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Aleksandra Wędrychowicz, Bogumił Cieniek, Ireneusz Stefaniuk, Ihor Virt, and Romana Śliwa
- Subjects
EPR ,PbTe ,PbSe ,DMS ,paramagnetic species ,Organic chemistry ,QD241-441 - Abstract
The magnetic properties of lead selenide (PbSe) and indium-doped lead telluride (PbTe:In) composites have been studied by using the electron paramagnetic resonance (EPR) technique. The samples were obtained by using the pulsed laser deposition method (PLD). Temperature dependences of the EPR spectra were obtained. The analysis of the temperature dependencies of the integral intensity of the EPR spectra was performed using the Curie–Weiss law. In these materials, the paramagnetic centers of Pb1+ and Pb3+ ions were identified. The results are discussed.
- Published
- 2022
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40. Sclerostin and its association with insulin resistance in children and adolescents
- Author
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Wędrychowicz, Anna, Sztefko, Krystyna, and Starzyk, Jerzy B.
- Published
- 2019
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41. Sclerostin and its significance for children and adolescents with type 1 diabetes mellitus (T1D)
- Author
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Wędrychowicz, Anna, Sztefko, Krystyna, and Starzyk, Jerzy B.
- Published
- 2019
- Full Text
- View/download PDF
42. Almost everywhere convergence of convolution products
- Author
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Reinhold, Karin, Savvopoulou, Anna, and Wedrychowicz, Christopher
- Subjects
Mathematics - Classical Analysis and ODEs - Abstract
Let $(X,\mathcal{B},m,\tau)$ be a dynamical system with $\ds (X,\mathcal{B},m)$ a probability space and $\ds \tau$ an invertible, measure preserving transformation. The present paper deals with the almost everywhere convergence in $\ds{L}^1(X)$ of a sequence of operators of weighted averages. Almost everywhere convergence follows once we obtain an appropriate maximal estimate and once we provide a dense class where convergence holds almost everywhere. The weights are given by convolution products of members of a sequence of probability measures $\ds\{\nu_i\}$ defined on $\ds\mathbb{Z}$. We then exhibit cases of such averages, where convergence fails., Comment: 13 pages, to appear In the Canadian Mathematical Bulletin
- Published
- 2011
43. Almost everywhere convergence of convolution powers without finite second moment
- Author
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Wedrychowicz, Christopher M.
- Subjects
Mathematics - Classical Analysis and ODEs - Abstract
We generalize a theorem of Bellow and Calder\'on concerning the a.e. convergence of the convolution powers $\ds \mu^nf(x)=\sum_{k}\mu^n(k)f(T^k x)$ where $T$ is a measure preserving transformation of a probability space and $\mu$ is a probability measure on the integers., Comment: 13 pages, to appear in Annales de l Institut Fourier
- Published
- 2010
44. Convergence and divergence of averages along subsequences in certain Orlicz spaces
- Author
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Wedrychowicz, C. M.
- Subjects
Mathematics - Dynamical Systems - Abstract
The classical theorem of Birkhoff states that the $T^N f(x) = (1/N)\sum_{k=0}^{N-1} f(\sigma^k x)$ converges almost everywhere for $x\in X$ and $f\in L^{1}(X)$, where $\sigma$ is a measure preserving transformation of a probability measure space $X$. It was shown that there are operators of the form $T^N f(x)=(1/N)\sum_{k=0}^{N-1}f(\sigma^{n_k}x)$ for a subsequence $\{n_k\}$ of the positive integers that converge in some $L^p$ spaces while diverging in others. The topic of this talk will examine this phenomenon in the class of Orlicz spaces $\{L{Log}^\beta L:\beta>0\}$.
- Published
- 2009
45. The assessment of the hypothalamicpituitaryadrenal axis after oncological treatment in pediatric patients with acute lymphoblastic leukemia
- Author
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B, Hull, primary, A, Wędrychowicz, additional, M, Ossowska, additional, A, Furtak, additional, J, Badacz, additional, S, Skoczeń, additional, and JB, Starzyk, additional
- Published
- 2023
- Full Text
- View/download PDF
46. Microstructure and Mechanical Properties of Al-Si Alloys Produced by Rapid Solidification and Hot Extrusion
- Author
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Noga, Piotr, primary, Skrzekut, Tomasz, additional, and Wędrychowicz, Maciej, additional
- Published
- 2023
- Full Text
- View/download PDF
47. Endogenous Opioids in Crohn’s Disease
- Author
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Martyniak, Adrian, primary, Wędrychowicz, Andrzej, additional, and Tomasik, Przemysław J., additional
- Published
- 2023
- Full Text
- View/download PDF
48. Prebiotics, Probiotics, and Postbiotics in the Prevention and Treatment of Anemia
- Author
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Zuzanna Zakrzewska, Aleksandra Zawartka, Magdalena Schab, Adrian Martyniak, Szymon Skoczeń, Przemysław J. Tomasik, and Andrzej Wędrychowicz
- Subjects
iron deficiency ,iron absorption ,lactobacillus ,bifidobacterial ,FOS ,GOS ,Biology (General) ,QH301-705.5 - Abstract
Iron deficiency anemia (IDA) is very common and affects approximately 1/3 of the world’s human population. There are strong research data that some probiotics, such as Lactobacillus acidophilus and Bifidobacterium longum improve iron absorption and influence the course of anemia. Furthermore, prebiotics, including galactooligosaccharides (GOS) and fructooligosaccharides (FOS), increase iron bioavailability and decrease its destructive effect on the intestinal microbiota. In addition, multiple postbiotics, which are probiotic metabolites, including vitamins, short-chain fatty acids (SCFA), and tryptophan, are involved in the regulation of intestinal absorption and may influence iron status in humans. This review presents the actual data from research studies on the influence of probiotics, prebiotics, and postbiotics on the prevention and therapy of IDA and the latest findings regarding their mechanisms of action. A comparison of the latest research data and theories regarding the role of pre-, post-, and probiotics and the mechanism of their action in anemias is also presented and discussed.
- Published
- 2022
- Full Text
- View/download PDF
49. Studies of Selective Recovery of Zinc and Manganese from Alkaline Batteries Scrap by Leaching and Precipitation
- Author
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Tomasz Skrzekut, Andrzej Piotrowicz, Piotr Noga, Maciej Wędrychowicz, and Adam W. Bydałek
- Subjects
alkaline batteries recycling ,zinc recovery ,manganese recovery ,leaching ,precipitation ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Recovery of zinc and manganese from scrapped alkaline batteries were carried out in the following way: leaching in H2SO4 and selective precipitation of zinc and manganese by alkalization/neutralization. As a result of non-selective leaching, 95.6–99.7% Zn was leached and 83.7–99.3% Mn was leached. A critical technological parameter is the liquid/solid treatment (l/s) ratio, which should be at least 20 mL∙g−1. Selective leaching, which allows the leaching of zinc only, takes place with a leaching yield of 84.8–98.5% Zn, with minimal manganese co-leaching, 0.7–12.3%. The optimal H2SO4 concentration is 0.25 mol∙L−1. Precipitation of zinc and manganese from the solution after non-selective leaching, with the use of NaOH at pH = 13, and then with H2SO4 to pH = 9, turned out to be ineffective: the manganese concentrate contained 19.9 wt.% Zn and zinc concentrate, and 21.46 wt.% Mn. Better selectivity results were obtained if zinc was precipitated from the solution after selective leaching: at pH = 6.5, 90% of Zn precipitated, and only 2% manganese. Moreover, the obtained concentrate contained over 90% of ZnO. The precipitation of zinc with sodium phosphate and sodium carbonate is non-selective, despite its relatively high efficiency: up to 93.70% of Zn and 4.48–93.18% of Mn and up to 95.22% of Zn and 19.55–99.71% Mn, respectively for Na3PO4 and Na2CO3. Recovered zinc and manganese compounds could have commercial values with suitable refining processes.
- Published
- 2022
- Full Text
- View/download PDF
50. Response to Treatment with Recombinant Human Growth Hormone (rhGH) of Short Stature Children Born Too Small for Gestational Age (SGA) in Selected Centres in Poland
- Author
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Marta Glińska, Mieczysław Walczak, Beata Wikiera, Beata Pyrżak, Anna Majcher, Monika Paluchowska, Aneta Gawlik, Aleksandra Antosz, Marcin Kusz, Artur Bossowski, Karolina Stożek, Anna Wędrychowicz, Jerzy Starzyk, and Elżbieta Petriczko
- Subjects
recombinant human growth hormone ,SGA ,FAS ,Silver-Russel syndrome ,Medicine - Abstract
Short stature resulting from SGA is an obligatory indication for treatment with rhGH. The aim of the study was to assess the response to rhGH treatment in patients treated in the years 2016–2020 in six clinical centers in Poland. During the analysis, auxological data were collected, and anthropometrical parameters (Ht, SDS Ht, HV and ΔHV) were reassessed. Subgroups of patients with dysmorphic features (DYSM), fetal alcohol syndrome (FAS) and Silver-Russel syndrome (SRS) were selected. The study group consisted of 235 children (137 boys). The medium initial age was 9.08 years, and 190 patients were in the prepubertal stage. The poor response to treatment was defined as ΔHt SDS < 0.3 and/or ΔHV < 3 cm/year. Seventeen per cent of all patients after the first year and 44% after the second year met the ΔHt SDS < 0.3 criterion, and 56% during the first and 73% during the second year met the ΔHV < 3 cm/year criterion. Our data suggest that patients with SRS may show the best response to treatment, which was sustained throughout the follow-up period. The best response in all subgroups was observed during the first 12 months of therapy. Although the proportion of patients meeting the poor response criteria was high, only a few patients exceeded the 97th percentile for IGF-1 concentration during the first year of treatment. This might suggest that increasing the dose of rhGH in the second treatment year in order to sustain accelerated HV would be safe in these patients.
- Published
- 2022
- Full Text
- View/download PDF
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